Generally, the current mixing method for fluid is that two to three sets of agitators are used for a mixing operation on a batch-by-batch basis. First, the fluids to be mixed are poured into an agitating tank using proper measuring means. Once standard pre-agitating conditions (temperature, viscosity and liquid level) are obtained, an agitating motor with a constant HP is started to agitate until reaching the mixing standard required, such as the viscosity, color, etc.; then, the mixed fluid may be poured into another container for storage or directly fed to the production line. The main drawbacks of this agitator are:
1. Small processing volume and space consuming - Since it is batch-by-batch operation, each batch requires a great deal of time for processing, agitating, and conveying, the feeding volume per time unit becomes very small. Therefore, it is necessary to provide two or three sets of agitators, and each batch of fluid or material needs a considerably large space. The total agitating equipment takes a lot of factory space, and therefore the whole production system is affected. PA0 2. No continuous feed--As a result of the batch-by-batch operation method, considerable time is needed to change the feeding pipes and to change the agitators; when changing, feeding is stopped. Since each agitator needs manpower and control instruments, it is deemed as being not economical in terms of operation, time, and equipment. PA0 4. Inconsistent Quality--Under the batch-by-batch processing method, the agitator vane must be rather thick and strong, and using that kind of vane it is very difficult to achieve an even agitating and cutting result in the fluid, moreover, there is no control at all over the size of the fluid particles. PA0 5. Large consumption of emulsifier--Since the quality stability is difficult to control, and the time between the agitating operation and the conveying operation is also not easy to control, the fluid is liable to re-condense and to gasify; therefore, the batch method requires a lot of emulsifier (interfacial agent) to maintain the fluid agitated and mixed at a given standard state.
3. High HP required--The batch to be processed may rang from several hundreds of liters to several tons, using an agitating power of at least 10 HP; for instance, a volume of 300-700 liters at a viscosity of 4000 Redwood, may need 20 HP.